Portable refrigerating unit



May 23, 1939. v N oR s 2,159,907

' I PORTABLE REFRIGERATING UNIT 7 Filed Jan. 8, 1957 2 Sheets-Sheet 1 May 23, 1939.

N. MORRIS PORTABLE REFRIGERATING UNIT 2 Sheets-Sheet 2 Filed Jan. 8, 1937 2| wu cmm mamj arrzfs Gum/m Patented May 23, 1939 PORTABLE REFRIGERATING UNIT Nathan Morris, Silver Spring, Md., assignor to American Instrument Company, Silver Spring, Md., a corporation of Delaware Application January 5, 1937, Serial No. 119,674

4 Claims.

This invention relates to mechanical refrigerating apparatus and, among other objects, aims to provide a greatly improved, simplified, compact, relatively inexpensive and reliable refrigerating 5 unitfor laboratory and other uses adapted to be rolled from place to place on a floor and used for cooling baths and the like Another aim of the invention is to provide a portable, unit having an evaporator in the form of a cooling coil connected 10 thereto by flexible conduits so that the coil can storage chamber within which the evaporator or p 15 coil, flexible conduits and electrical cables may be stored when they are not in use, so that the whole unit can be rolled under a work bench or table out of the way and the parts thereof will not be subject to damage Other aims and advantages of the invention will appear in thespeciflcation when considered in connection with the accompanying drawings, wherein:

Fig. 1 is a side elevation of a refrigerating unit 5 embodying the invention and showing the cooling 7 coil inserted in a tank or receptacle;

Fig. 2 is a top plan view of the unit shown in F g. 1;

Fig. 3 is an end view of the unit showing the 30 condenser and the evaporator coil, stored in the storage compartment;

Fig. 4 is a sectional view taken on the line 4-4 of Fig. 3; and

Fig. 5 is a wiring diagram showing the motor 35 control circuit.

Referring particularly to the drawings, the refrigerating unit here shown is especially designed for use in laboratories wherein baths of various kinds have to be cooled and the temperatures maintained substantially constant. The idea is to provide a unit which may be used successively to cool the liquid in severaldifferent baths by rolling it around the floor and inserting the coil in the desired bath. The construction and ar- 5 rangement are such that the unit maybe connected to ordinary electrical service outlets provided for lamps and the like.

In this example, the unit is mounted in a boxlike casing havinga frame composed of corner uprights or standards Ill made of structural angles. At the bottom of the frame there is connected a rectangular-base frame II also preferably made of structural angles and having a bottom wall l2 which may be made of perforated 55 metal suitably secured to the horizontal angle flange of the base frame. At the four corners of the bottom, ordinary swivel wheels'or casters l3 are shown as being connected to the flanges of the angles. Above the bottom of the frame there is also shown an intermediate supporting frame M which is also conveniently made of structural angles and having combined braces and supporting bars I5 near the corners, to which are bolted or otherwise secured the base "5 of a motor I! and compressor unit l8 as well as an 10 ordinary condenser ill at one end of the frame. The motor-driven compressor, which may be of any well known type, is adapted to be inserted vertically in the casing through the open top and then bolted in place. The top is then closed by a top cover consisting of a rectangular frame and a perforated metal top 2|, the frame being suitably bolted to the vertical standards; while all of the other joints of the frame members are preferably spot-welded. Strap metal braces or 20 bars 22 are shown as being connected to the vertical standards at the opposite ends of the frame, near the top, to carry suitable pivoted handles 23, the arrangement being such that the unit may be pulled or pushed in any direction or carried by hand. The end of the frame opposite from the condenser is preferably closed by an openwork or perforated metal wall 24 secured to the uprights and other frame elements. Both sides of the frame are adapted to be closed by such perforated metal walls which are readily removable to permit access to the mechanism. Aportion of one wall is indicated at 25 in Fig. 4. In Fig. 2. vertical guide flanges 26 are shown for holding the side walls in place, so that they are slidably mounted and may be removed by lifting and sliding them out of their guides.

In accordance with this invention, an ordinary evaporator or coil 21 having an expansion valve is connected to the refrigerating unit by means 0 of a' pair of flexible conduits 28 and 29, extending into the casing. The conduits are far more flexible than ordinary copper tubing so that they may bend very easily and will enable the coil to be inserted in any position in a tank or receptacle, such as the receptacle 30 in Figs. 1 and 2. In Figs. 1 and 2, the side walls are removed to permit the conduits to be connected to the fittings or couplings on opposite sides of the unit. However, it is contemplated that the conduits may extend downwardly into the casing and be stored therein when not in use as will hereinafter be described.

The space below the supporting frame I4 provides a storage compartment 3| for the evaporahousing for the control equipment has a panel 33 carrying an ordinary electric switch 34 and an electrical receptacle 35 to receive a plug 36 carried by a thermostat cable 31 on which is connected a thermal control element shown as being a bimetallic thermostat 33 also adapted to be inserted in the bath. The main electric cable 39 for the unit projects through the panel into the control housng. It will be understood that the control equipment includes a thermally controlled relay operated switch (Fig. 5), of any suitable type such as that shown in my copending application, Ser. No. 29,394, filed July 1, 1935.

It will be noted that the storage compartment 3| provides ample space for accommodating the evaporator or coil, the flexible conduits, the thermostat and the electric cables. It is preferably left open at one end as shown in Figs. 3 and 4. The evaporator is shown as being disconnected in the storage compartment. However, as hereinbefore stated, the conduits for the evaporator may remain connected to it and extend directly from the unit connections into the compartment, so that the conduits may be coiled up in the compartment and stretched out when the evaporator is removed. This storage space does not materially increase the size of the unit. The accessories may be entirely disconnected from the unit and stored in the storage compartment when the unit is not to be used or for shipping purposes.

From the foregoing description, it will be seen that the improved. refrigerating unit is very compact and rugged in its construction. It has ample provision for circulating cooling air for the condenser. It is of light weight and can easily be moved by a single person. In fact, its weight is so small that it can be picked up and carried from place to place. ,It is very effective in operation and can be used for many different purposes which will be apparent to those skilled in the art. when it is not in use and may be connected to any ordinary electric service outlet.

Obviously, the present invention is not restricted' to the particular embodiment thereof herein shown and described. Moreover, it is not indispensable that all the features of the invention be used conjointly, since they may be employed advantageously in various combinations and sub-combinations.

What is claimed is:

l. A composite portable refrigerating unit of It requires very little storage space the character described comprising, in combination, a substantially rectangular frame having a bottom wall; supporting frame members secured within said frame; a motor compressor unit and condenser removably secured to said supporting frame members; an evaporator having flexible conduits adapted to be connected to said unit; perforate walls secured'to said frame; and a storage compartment in the lower portion of said frame to accommodate said evaporator and conduits.

2. A portable refrigerating unit of the class described comprising, in combination, a casing having structural frame members and openwork protecting walls; a motor-compressor unit and condenser mounted within the casing; an evaporator coil having conduits removably connected to said unit; a control panel on the casing; an electric cable for the motor extending through the control panel; a switch for controlling the motor'on said panel; a relay-operated switch in the motor circuit; and a thermostat having a cable also connected to said panel to control said relay-operated switch.

3. A portable, compact refrigerating unit of the character described comprising, in combination, a casing having perforate walls and structural frame members; supporting wheels mounted on the bottom of the casing; an electric motorcompressor unit and condenser mounted'in the casing; an evaporator having flexible conduits removably connected to said unit; a closed control box for the motor secured within the casing and having a control panel forming a portion of one wall; an electrical conduit connected to the control panel and adapted to be plugged into an electrical service outlet; a switch for controlling the motor circuit; a thermostat having an electric cable adapted to be connected to the motor control mechanism through the panel; and a storage compartment in the lower portion of said casing to accommodate said evaporator with its conduits and said electric cable.

4. A compact portable refrigerating unit of the class described comprising, in combination, a substantially rectangular casing; supporting frame members in the casing; a motor-compressor unit removably mounted on said frame members; removable protecting walls on the sides and top of the casing; an evaporator flexibly connected to said' unit; and a storage compartment in the lower portion of said casing to receive said evaporator when it is not in use.

NATI-IAN MORRIS. 

